Gold-coated Iron Oxide Research Articles

A glassy carbon electrode modified with gold decorated iron oxide/ carbon dots for light assisted voltammetric detection of antibiotic resistant microbe Enterococcusfaecalis

Detecting bacteria is essential in managing significant health concerns as it enables timely intervention, reducing complications and improving patient outcomes, particularly in treating common infections that necessitate precise identification for effective symptom management. Enterococcus species represent a notable threat in hospital-acquired infections and urinary tract infections (UTIs), given the increasing prevalence of strains resistant to multiple antibiotics, unresponsive to standard therapies, and carrying various virulence factors. Traditional approaches to identifying Enterococcus faecalis (E. faecalis) have limitations, including prolonged processing times, limited sensitivity, and the potential for false positive results. While Polymerase Chain Reaction (PCR) is a valuable tool, it is susceptible to contamination and variations in DNA concentration. The emerging technique of Photoelectrochemical (PEC) holds promise for enhancing E. faecalis detection by leveraging photogenerated electrons and holes. This study introduces a rapid and precise approach utilizing a light-assisted electrochemical biosensor featuring a glassy carbon electrode modified with a nanocomposite of gold-coated iron oxide and carbon dots (Au@Fe3O4/CDs). The nanocomposite was successfully synthesized and underwent thorough characterization. The investigation has a detection range from 1 to 14 CFU mL−1, along with a notably low limit of detection (LOD: 3 CFU mL−1, LOQ: 10 CFU mL−1). Rigorous examination of real-world samples such as food, water, and soil demonstrated exceptional specificity, reproducibility, and long-term stability of the sensor. The applications of the Au@Fe3O4/CDs nanocomposite in PEC processes underscore the potential of this innovative approach in addressing health concerns associated with bacterial infections and delivering real-time impacts for both healthcare and environmental domains.

Synergic fabrication of gold – iron oxide magnetic nanohybrids as a potential agent for thermosensitizing and magnetic resonance-high intensity focused ultrasound (mr-HIFU) treatment in uterine myomas

The major aim of this research hyperthermia and magnetic resonance-high intensity focused ultrasound (MR-HIFU) focused on investigating the potential of aloe vera leaf extract-mediated gold-coated iron oxide nanohybrids (Au-IONPs) as a modern theragnostic material for the treatment of uterine myoma. To assess the cytotoxicity of Au-IONPs, induce hyperthermia, and apply radiotherapy to determine the level of apoptosis in the human ht-UtLM cells. Subsequently, it evaluated the cytotoxicity of the nanoparticles on human ht-UtLM cells by exposing the cells to various concentrations of Au-IONPs for a 4-hour incubation period. Based on the results, concentrations of 10 and 15 µg/mL were selected for further investigation. The MTT assay and flow cytometry results demonstrated that Au-IONPs significantly induce cell apoptosis. It allows the Au-IONPs to turn as an effective development mediator in the ablation of high-intensity focused ultrasound (HIFU) treatment. Finally, it could be suggested to developed material have excellent systemic toxicity, which promises well for treatment of uterine fibroids. HIGHLIGHTS Biosynthesis of gold – iron oxide nanohybrids (Au-IONPs) through a green approach. Physio-chemical properties of Au-IONPs have been characterized through various techniques. Investigating the anti-tumor effects of Au-IONPs in combination with thermo-radiotherapy for uterine myoma. Determine the level of apoptosis in the human myoma cells by inducing hyperthermia and radiotherapy. Observed the correlation behavior between the dose of the cell viability and Au-IONP nanoparticles. Au-IONPs had a significant impact on enhancing the effects of both hyperthermia and radiation therapies.

Catalytic oxidation of alcohols catalyzed by gold-coated iron oxide magnetic nanoparticles in water

Catalytic oxidation of alcohols catalyzed by gold-coated iron oxide magnetic nanoparticles in water

Pharmacokinetic modeling of solid and hollow gold-coated superparamagnetic iron oxide nanoparticles for brain-targeted therapeutics: prediction and experiment

Pharmacokinetic modeling of solid and hollow gold-coated superparamagnetic iron oxide nanoparticles for brain-targeted therapeutics: prediction and experiment

Highly efficient degradation of basic dyes using gold-coated nature-based supermagnetic iron oxide nanoparticles as eco-friendly nanocatalysts

Nowadays, organic dyes are prevalent components in wastewater discharges due to their extensive use in various industries, posing a significant threat to public health across different organisms. As a result, wastewater treatment has become an indispensable requirement. In this study, we synthesized supermagnetic iron oxide (Fe3O4 NPs) and gold-iron oxide bimetallic nanoparticles (Au@Fe3O4 BNPs) using an eco-friendly method that involved natural compounds extracted from brown Egyptian propolis. We employed UV-visible spectroscopy, FTIR, XRD, VSM, SEM, HRTEM, EDX, Zeta potential and XPS techniques to examine the optical characteristics, chemical structure, crystalline structure, magnetic properties, morphology, size, and chemical composition of these biosynthesized nanoparticles. Furthermore, these nanoparticles were used as nanocatalysts for the removal of cationic dyes. The photocatalytic results indicated high efficiency in the removal of methylene blue (MB), crystal violet (CV), and malachite green (MG) dyes from aqueous solutions using Fe3O4 NPs and Au@Fe3O4 BNPs. The removal rates of MB, CV, and MG were about 95.2% in 70 min, 99.4% in 50 min, and 96.2% in 60 min for Fe3O4 NPs, and 97.1% in 50 min, 99.1% in 30 min, and 98.1% in 50 min for Au@Fe3O4 BNPs, respectively. The study also assessed the potential anti-radical properties of the extract, Fe3O4 NPs, and Au@Fe3O4 BNPs using the DPPH assay, and the results demonstrated their antioxidant activity. Finally, these Fe3O4 NPs and Au@Fe3O4 BNPs have the potential to serve as efficient antioxidants and photocatalysts for removing basic dyes from water.Graphical abstract

Surface-modified gold-coated superparamagnetic iron oxide nanoparticles promoting light-controlled drug release

Surface-modified gold-coated superparamagnetic iron oxide nanoparticles promoting light-controlled drug release

Ultrafast Heating Rate of Ultrasmall Gold-Coated Iron Oxide Magnetic Nanoparticles by Ferromagnetic Resonance

In this study, we demonstrated experimental findings on the ultrafast heating capabilities of ultrasmall gold-coated iron oxide magnetic nanoparticles (Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> @Au NPs) utilizing the ferromagnetic resonance (FMR) effect. A lab-made setup was employed to evaluate the ferromagnetic resonance and temperature increment of NPs under FMR conditions. The resonant frequency of both Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> @Au NPs and their uncoated Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> NPs was several GHz and increased with the strength of the applied DC field as accurately described by the Kittel equation. At a given DC field, the resonant frequency of Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> @Au NPs slightly shifted lower than compared to Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> NPs. Remarkably, the initial temperature rising rate reached maximum values corresponding to the DC fields for FMR condition (e.g. 1.294 and 3.894 ºC/s under <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">DC</sub> =1200 Oe for RF field of <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">AC</sub> =4 GHz and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">H</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">AC</sub> =4 Oe for Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> @Au and Fe <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> NPs, respectively). These values were two orders of magnitude higher than that of Néel-Brownian relaxation for conventional magnetic hyperthermia. Furthermore, the maximum value of the heating rate increased with higher RF field frequencies. These results demonstrate the potential of controlling the temperature of NPs by adjusting RF field and DC field parameters, offering promising prospects for therapeutic temperature control in magnetic hyperthermia applications.

Au@Fe3O4 NANOPARTICLES: PREPARATION, CHARACTERIZATION AND CYTOTOXIC EVALUATION

Gold-coated iron oxide nanoparticles are a class of potential theranostic nanoparticles that have been studied for their multitude of magnetic and optical properties with possible medical applications. In this work, spherical Au@Fe3O4 nanoparticles were successfully synthesized from Fe electrodes immersed in HAuCl4 solution using a very simple method - pulsed plasma in liquid, without any dopants or special conditions for stabilization. Vibrating sample magnetometer indicated ferromagnetic behavior of the particles at room temperature with coercivity and saturation magnetization of Hc=175 and Ms= 3.56 emu/g, respectively. Face-centered cubic Au and spinel inverse structure of FCC- Fe3O4 were determined by X-Ray diffraction analysis. High-resolution transmission electron microscopic analysis revealed that Fe3O4 particles with 14 nm in size are connected to 18 nm Au particles. The cytotoxicity of the nanoparticles was evaluated using a XTT assay on Hela cells, revealing very low (cell viability: 98-89% with Fe3O4 and 99-91% for Au@Fe3O4 NPs). This indicates that Au improves biocompatibility of magnetic nanoparticles, enabling their application in biomedicine

Chain length impact on the retro Diels-Alder mediated release of gemcitabine from hybrid nanoparticles towards pancreatic cancer therapy

Previously reported gold coated iron oxide nanoparticles (Au-IONP’s) have demonstrated their effectiveness as drug delivery vehicles for gemcitabine conjugated to a thermally labile Diels-Alder linker containing a chain of 4 carbon atoms (TTLD4) for the treatment of pancreatic cancer. Heat generated via laser irradiation of Au-IONPs facilitated retro Diels-Alder mediated release in a burst release profile where approximately half of all total release over 180 min occurred within the first 5 min. Two analogues of TTLD4, which differ only in linker chain length (TTLD3 & TTLD6) were synthesised and conjugated to Au-IONP’s. Heat-mediated release of gemcitabine at 45 °C over 180 min from these formulations was confirmed to be based on linker length, which was 94%, 76% and 45% for TTLD3, TTLD4 and TTLD6, respectively. Drug loading of the Diels-Alder linkers in a 5:1 Drug/Au-IONP w/w ratio appears to favour those containing an even number of carbons TTLD4 (76%) & TTLD6 (57%) over TTLD3 (25%), possibly due to the linker likely being positioned perpendicular to the Au-IONP surface because of the 120 °C–C bond.

Theranostic RGD@Fe3O4-Au/Gd NPs for the targeted radiotherapy and MR imaging of breast cancer

BackgroundAs a radiosensitizing agent in magnetic resonance imaging (MRI), gadolinium is disadvantageous in that it confers a rather high toxicity and low longitudinal comfort time (r1). We hypothesized that gadolinium when combined with gold-coated iron oxide nanoparticles (NPs), might deliver better radiosensitization in MRI-based cancer theranostics. After being synthesized ligand/receptor RGD@Fe3O4-Au/Gd nanoparticles, they were characterized via some methods, such as visible–ultraviolet spectroscopy (UV–VIS), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), and transmission electron microscope (TEM). Using relaxometry, the parameters of contrast change in T1-weighted MRI and the rate of radiation sensitivity on cancerous (MCF-7, SK-BR-3 and MDA-MB-231 (and reference (MCF-10a) breast cell lines were investigated.ResultsThe presence of ultra-small iron oxide, gold, gadolinium, and RGD peptide as components of the RGD@Fe3O4-Au/Gd nanocomplex was confirmed by UV–visible, FTIR, EDX and XRD tests. With a size ranging from 4.124 nm (DLS) to 15 nm (TEM), these NPs exhibited a surface charge of –45.7 mV and a magnetic saturation of 3 emu/g. The concentrations of iron, gadolinium and gold samples in the nanocomplex were 1000, 1171 and 400 parts per million (ppm), respectively. In the relaxometry test, the rates of r2/r1 and r1 NPs were 1.56 and 23.5 mM−1 s−1. The dose increase factor for targeted (RGD@Fe3O4-Au/Gd) and non-targeted (Fe3O4-Au/Gd) NPs at 6 MV and 2 Gy was 89.1 and 59.1, respectively.ConclusionOwing to an enhanced signal-to-noise ratio (SNR), as confirmed by the MRI of RGD receptor-expressing MDA-MB-231 cells, RGD@Fe3O4-Au/Gd NPs were found to confer higher radiosensitization and an overall better performance as a novel radiosensitizer for MRI-based breast cancer theranostics than Fe3O4-Au/Gd nanocomplex.Graphical

Radiosensitising effect of iron oxide‐gold nanocomplex for electron beam therapy of melanoma in vivo by magnetic targeting

Melanoma is a dangerous type of skin cancer sometimes treated with radiotherapy. However, it induces damage to the surrounding healthy tissue and possibly further away areas. Therefore, it is necessary to give a lower dose to the patient with targeted therapy. In this study, the radio-sensitising effect of gold-coated iron oxide nanoparticles on electron beam radiotherapy of a melanoma tumour with magnetic targeting in a mouse model was investigated. Gold-coated iron oxide nanoparticles were prepared in a steady procedure. The melanoma tumour model was induced in mice. Animals were divided into five groups: (1) normal; (2) melanoma; (3) gold-coated iron oxide nanoparticles alone; (4) electron beam radiotherapy; (5) electron beam radiotherapy plus gold-coated iron oxide nanoparticles. The magnet was placed on the tumour site for 2h. The tumours were then exposed to 6MeV electron beam radiotherapy for a dose of 8Gy. Inductively coupled plasma optical emission spectrometry test, hematoxylin and eosinstaining, and enzyme-linked immunosorbent assayblood test were also performed. Gold-coated iron oxide nanoparticles with magnetic targeting before electron beam radiotherapy reduced the growth of the tumour compared to the control group. Blood tests did not show any significant toxicity. Deposition of nanoparticles was more in the tumour and spleen tissue and to a lesser extent in the liver, kidney, and lung tissues. The synergistic effect of nanoparticles administered by the intraperitoneal route and then concentrated into the tumour area by application of an external permanent magnet, before delivery of the electron beam radiotherapy improved the overall cancer treatment outcome and prevented metal distribution side effects.

Gold-Coated Superparamagnetic Iron Oxide Nanoparticles Functionalized to EGF and Ce6 Complexes for Breast Cancer Diagnoses and Therapy

Superparamagnetic iron oxide nanoparticles (SPIONs) have some limitations in the physiological environment, however, a modification on their surface, such as a core-shell structure with gold (SPIONs@Au), can enhance their applicability. In this study, SPIONs were synthesized by the chemical coprecipitation method, stabilized by sodium citrate, and followed by the gold-coating process. SPIONs@Au were functionalized with EGF-α-lipoic acid and chlorin e6 (Ce6)-cysteamine complexes, composing a Theranostic Nanoprobe (TP). The outcomes showed that the SPIONs@Au had changed in color to red and had an absorption band centered at 530 nm. The coating was verified in the TEM micrographs in bright and dark fields by EDS mapping, which indicated the presence of Au and Fe. The Ce6-cysteamine complex had a resonant band at 670 nm that enabled the diagnosis of biological samples using fluorescence analysis. In the measure of TNBC cell uptake, the maximum value of TP fluorescence intensity was obtained within 4 h of internalization. At 2 h, the incorporation of the TP in the cytoplasm as well as in the nuclei was observed, suggesting that it could be employed as a diagnostic marker. The PTT results showed significant percentages of apoptosis in the TNBC cell line, which confirms the efficacy of the TP.

Effect of Citrate- and Gold-Stabilized Superparamagnetic Iron Oxide Nanoparticles on Head and Neck Tumor Cell Lines during Combination Therapy with Ionizing Radiation.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. They are associated with alcohol and tobacco consumption, as well as infection with human papillomaviruses (HPV). Therapeutic options include radiochemotherapy, surgery or chemotherapy. Nanoparticles are becoming more and more important in medicine. They can be used diagnostically, but also therapeutically. In order to provide therapeutic alternatives in the treatment of HNSCC, the effect of citrate-coated superparamagnetic iron oxide nanoparticles (Citrate-SPIONs) and gold-coated superparamagnetic iron oxide nanoparticles (Au-SPIONs) in combination with ionizing irradiation (IR) on two HPV positive and two HPV negative HNSCC and healthy fibroblasts and keratinocytes cell lines were tested. Effects on apoptosis and necrosis were analyzed by using flow cytometry. Cell survival studies were performed with a colony formation assay. To better understand where the SPIONs interact, light microscopy images and immunofluorescence studies were performed. The HNSCC and healthy cell lines showed different responses to the investigated SPIONs. The cytotoxic effects of SPIONs, in combination with IR, are dependent on the type of SPIONs, the dose administered and the cell type treated. They are independent of HPV status. Reasons for the different cytotoxic effect are probably the different compositions of the SPIONs and the related different interaction of the SPIONs intracellularly and paramembranously, which lead to different strong formations of double strand breaks.

Ultra-Low Detection of Infectious Disease Nucleic Acid Biomarkers By a Visual Colorimetric Sensor

The gold standard method for detecting nucleic acid markers is the polymerase chain reaction. However, this method demands high technical skills, labor-intensive, time-consuming, and expensive. Many resource-limited countries around the globe do not have access to such laboratory-based PCR tests. To address the global test needs of virus and other pathogen infections, as well as address the early biomarker detection of diseases. We have developed an affordable nanoparticle colorimetric sensor approach. In our system, the virus RNA marker is captured by the complementary oligonucleotide attached to low fouling gold-coated iron oxide nanoparticles. Further specificity is achieved through a second complementary hybridization probe conjugated with streptavidin-horseradish peroxidase labels. Visual colorimetry is performed using a chromogenic substrate allowing the visual conversion of the colorless solution to a blue color confirming a positive test. The intensity of the color is in direct correlation to the concentration of the virus RNA marker. We have successfully demonstrated attomolar detection in buffer and picomolar detection in real undiluted biofluids such as in neat human serum. Our ongoing efforts focus on saliva-based non-invasive detection with ultra-low capabilities, optimization of the assay, repeatability, and expanding this work for a multiplex detection format

Textural Thermo-gravimetric and Magnetic Properties of Green Synthesised Water Dispersible Pristine and Gold Coated Superparamagnetic Iron Oxide Nanoparticles

Gold-coated magnetic nanoparticles have received a lot of attention in recent years due to their multifunctional attributes and their prospective unique characteristics in environmental and biomedical applications. This paper reports the textural, thermo-gravimetric, and magnetic properties of green synthesized gluconic acid-capped uncoated and gold-coated superparamagnetic iron oxide nanoparticles (SPION@Au). The as-synthesized nanomaterials were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermal gravimetric analysis (TGA), Brunauer–Emmett–Teller (BET), and superconducting quantum interference device (SQUID) magnetometry. The XRD and SEM measurements showed that the gluconic acid-capped magnetic core was coated with gold with cubical spinel crystalline structures. TGA results revealed the thermal stability of the nanoparticles. Textural properties indicated that the gold-coated nanoparticles were in naturally mesoporous and exhibited the type IV isotherm with an H2 hysteresis loop. The estimated maximum pore diameter and surface area of SPION@Au were 3.33 nm and 134.02 m²/g respectively. Furthermore, the SQUID results showed the nanocrystals were superparamagnetic with a blocking temperature (TB) of 214 K at 500 Oe and saturation magnetization of 11.38 emu/g. These noteworthy results demonstrated that the as-synthesized SPION@Au are promising nanomaterials for biomedical and analytical applications.

Modulation of α-Chymotrypsin Conjugated to Magnetic Nanoparticles by the Non-Heating Low-Frequency Magnetic Field: Molecular Dynamics, Reaction Kinetics, and Spectroscopy Analysis.

Enzymes conjugated to magnetic nanoparticles (MNPs) undergo changes in the catalytic activity of the non-heating low-frequency magnetic field (LFMF). We apply in silico simulations by molecular dynamics (MD) and in vitro spectroscopic analysis of the enzyme kinetics and secondary structure to study α-chymotrypsin (CT) conjugated to gold-coated iron oxide MNPs. The latter are functionalized by either carboxylic or amino group moieties to vary the points of enzyme attachment. The MD simulation suggests that application of the stretching force to the CT globule by its amino or carboxylic groups causes shrinkage of the substrate-binding site but little if any changes in the catalytic triad. Consistent with this, in CT conjugated to MNPs by either amino or carboxylic groups, LFMF alters the Michaelis–Menten constant but not the apparent catalytic constant kcat (= Vmax/[E]o). Irrespective of the point of conjugation to MNPs, the CT secondary structure was affected with nearly complete loss of α-helices and increase in the random structures in LFMF, as shown by attenuated total reflection Fourier transformed infrared spectroscopy. Both the catalytic activity and the protein structure of MNP-CT conjugates restored 3 h after the field exposure. We believe that such remotely actuated systems can find applications in advanced manufacturing, nanomedicine, and other areas.

Isolation Methods Influence the Protein Corona Composition on Gold-Coated Iron Oxide Nanoparticles.

Upon exposure to a biological environment, nanoparticles (NPs) acquire biomolecular coatings, the most studied of which is the protein corona. This protein corona gives NPs a new biological identity that will determine various biological responses including cellular uptake, biodistribution, and toxicity. The standard method to isolate NPs from a biological matrix in order to study their coronas is centrifugation, but more gentle means of retrieval may enable deeper understanding of both irreversibly bound hard coronas and more loosely bound soft coronas. In this study, magnetic gold-coated iron oxide NPs were incubated with rainbow trout gill cell total protein extracts and mass spectrometric proteomic analysis was conducted to determine the composition of the protein coronas isolated by either centrifugation or magnetic retrieval. The number of washes were varied to strip away the soft coronas and isolate the hard corona. Hundreds of proteins were adsorbed to the NPs. Some proteins were common to all isolation methods and many others were particular to the isolation method. Some qualitative trends in protein character were discerned from quantitative proteomic analyses, but more importantly, a new kind of protein corona was identified, mixed corona, in which the labile or inert nature of the protein-NP interaction is dependent upon sample history.

Magnetic Fields and Magnetically Stimulated Gold-Coated Superparamagnetic Iron Oxide Nanoparticles Differentially Modulate L-Type Voltage-Gated Calcium Channel Activity in Midbrain Neurons

Magnetic Fields and Magnetically Stimulated Gold-Coated Superparamagnetic Iron Oxide Nanoparticles Differentially Modulate L-Type Voltage-Gated Calcium Channel Activity in Midbrain Neurons

Gold-coated iron oxide core–shell nanostructures for the oxidation of indoles and the synthesis of uracil-derived spirooxindoles

Synthesis of isatins and uracil-based spirooxindoles catalysed by Au/Fe3O4core–shell nanoparticles under mild conditions and low reaction times.

Nonlinear optical response of cancer cells following conventional and nano-technology based treatment strategies: Results of chemo-, thermo- and radiation therapies

BackgroundAlthough traditional treatments are able to increase cancer survival rate, undesirable impact on off-target tissues are considered a limitation of these approaches. Nanotechnology-based treatments have been proposed as a possible option to enhance targeting., Further,current methods for evaluating cellular damage, are time consuming, highly dependent on the operator skills, and expensive. The aim of this study was to evaluate the capability of nonlinear optical response of cells to determine cellular damages during conventional and nano-technology based treatments. MethodsThree different cancer cell lines, CT26, KB, and MCF-7 were used in this study. The alginate hydrogel co-loaded with cisplatin and Au nanoparticle (ACA) nanocomplex and gold-coated iron oxide nanoparticle (Au@IONP) were considered for chemo- and chemo-photothermal therapies, and thermo-radiation therapy, respectively. The sign and value of nonlinear optical absorption coefficient and imaginary part of the third-order nonlinear susceptibility of cells were computed. MTT assay was utilized as a reference method. ResultsThe value of nonlinear optical indices increased with increasing cellular damage and cell death. The linear regression analysis indicated high correlation between nonlinear optical indices and MTT results, in all treatments. ConclusionThe nonlinear optical indices are robust from confounding factors, namely treatment approach (traditional and nano-technology based), treatment modality (chemotherapy, thermotherapy, photothermal therapy, and radiation therapy), and cell types. Nonlinear optical properties of cells can be used as a rapid estimation method for cell damage, at the nanoscale level.